#include <fstream>
#include <math.h>
using namespace std;

ifstream fin("arbint.in");
ofstream fout("arbint.out");

const int MAXN = 1e5;
const int MAXSQN = 317;

int max(int a, int b) {
  return a > b ? a : b;
}

struct SqrtDecomp {
  int n;
  int sq;
  int *a;
  int chunks[MAXSQN] = {};

  void init(int _n, int _a[MAXN]) {
    n = _n;
    a = _a;
    sq = sqrt(n);
    // printf("init cu n = %d; sqrt %d\n", n, sq);

    for (int i = 0; i < n; ++i) {
      // printf("  %d (%d) e in chunk %d\n", i, a[i], i / sq);
      if (a[i] > chunks[i / sq]) {
        chunks[i / sq] = a[i];
      }
    }
  }

  int max_query(int l, int r) {
    int l_chunk = (l + sq - 1) / sq,
        r_chunk = (r - 1) / sq;
    int ans = -1;
    int i;

    // printf("query(%d -> %d); chunks %d -> %d; L incepe la %d, R se termina la %d\n", l, r, l_chunk, r_chunk, l_chunk * sq, (r_chunk + 1) * sq - 1);

    for (l; l < l_chunk * sq; ++l) {
      ans = max(ans, a[l]);
      // printf("l = %d; ans %d\n", l, ans);
    }
    for (i = l_chunk; i <= r_chunk; ++i) {
      ans = max(ans, chunks[i]);
      // printf("ch = %d; ans %d\n", i, ans);
    }
    for (r; r >= (r_chunk + 1) * sq - 1; --r) {
      ans = max(ans, a[r]);
      // printf("r = %d; ans %d\n", r, ans);
    }

    return ans;
  }

  void set_val(int pos, int val) {
    int ch = pos / sq;
    // printf("update pos %d = %d\n", pos, val);
    if (chunks[ch] == a[pos]) {
      // printf("  trebuie sa resetez max (merg de la %d -> %d)\n", ch * sq, min(n, (ch + 1) * sq - 1));
      a[pos] = val;
      chunks[ch] = -1;
      for (int i = ch * sq; i < min(n, (ch + 1) * sq); ++i) {
        // printf("    a[%d] = %d\n", i, a[i]);
        chunks[ch] = max(chunks[ch], a[i]);
      }
      // printf("  => = %d\n", chunks[ch]);
    } else {
      a[pos] = val;
    }
  }
} batog;

int a[MAXN];
int n, m;

void citire() {
  fin >> n >> m;
  for (int i = 0; i < n; ++i) {
    fin >> a[i];
  }
}

void process_queries() {
  int qt, a, b;

  for (int i = 0; i < m; ++i) {
    fin >> qt >> a >> b;

    if (qt == 0) {
      fout << batog.max_query(a - 1, b - 1) << '\n';
    } else {
      batog.set_val(a - 1, b);
    }
  }
}

int main() {
  citire();
  batog.init(n, a);
  process_queries();
}